This is in line with other studies that reported that high serum levels of soluble uPAR (suPAR) were significantly associated with worse survival in colorectal, prostate, ovarian and breast cancer, as well as in multiple myeloma (Sier et al, 1998; Brünner et al, 1999; Miyake et al, 1999; Stephens et al, 1999; Riisbro et al, 2002; Rigolin et al, 2003; Shariat et al, 2007) In contrast to cell-bound uPAR, which focuses uPA mediated plasmin formation to the cell surface, the role and source of suPAR remain to be clarified (Brünner et al, 1999). Here, PLAUR is linked to breast cancer.